The invention relates to a method and tool for producing stamped disks, including at least one stamping or fine blanking stage and at least one corrugating and embossing stage.
A method and a device for producing corrugated disks in two method steps is known from DE 10 2010 028 280 A1, wherein a workpiece is stamped or fine blanked in a first method step, transported between the first method step and a second method step, and corrugated and simultaneously deburred in the second method step. The method is carried out using a two-stage tool, the first stage of which is designed as a fine blanking stage and the second stage of which is designed as an embossing and corrugating stage.
Rollover typically develops during fine blanking, which in particular increases as the corner radius decreases and the sheet metal thickness increases. The rollover depth can be approximately 20%, and the rollover width can be approximately 30% of the sheet metal thickness or more (see DIN 3345, Fine blanking, August 1980), such that the lack of sharp edges on the outer teeth of the disks can result in limitation of the component function.
Moreover, forming of the thin and planar disk blank in the corrugating stage results in warpage, which impairs the shape accuracy of the outer and inner contours, and more significantly the shape and dimensional accuracy of the outer teeth of the disk. As a result, the installation and functional properties are adversely affected. Complex reworking is then required.
A method for producing stamped parts, in particular planar disks, is described in DE 196 08 551 A1 in which, in a first method step, the workpiece is stamped from the raw material inside a device. After stamping, the workpiece is moved to an embossing stage by way of transfer tongs, which are likewise accommodated in the device. The burr on the disk is compressed in the embossing stage. This prior art has the disadvantage that the disk on which the burr has been compressed must be corrugated in an additional processing stage—as described in EP 1 128 081 B1, for example—which considerably increases the complexity and costs in production.